Printing-plate device.



H. C. BOEDECKER.

PRINTING PLATE DEVICE.

APPLICATION FILED AUG. m. 1916.

1 915 98539 Patented Max:122, 1918.

2 SHEETS-SHEET I.

i my H. C. BOEDICKER.

PRINTENG PLATE DEVIG APPUCATWN ERLEB AUG. m 2916.

HERMAN C. BOEDICKEB, 0'3 MINNEAPOLIS, MINNESOTA.

EBINTING-ELATE DEVICE.

Specification of Letters Patent.

Patented Mar, 12, MM.

Application filed. August ie, 1918. Serial No. 114,372.

T 0 all whom it may concern:

Be it known that I, KIIERMAN G. Eon DICKER, a. citizen of the UnitedStates, residing at Minneapolis, in the county of Hennepin and State ofMinnesota, have invented certain new and useful Improvements inPrintingllate Devices, of which the following is a specification.

(hie object of my invention is to provide means for locating a printingplate and recording'its location so that it can at any future time bere-located exactly in its first position.

Another object of my invention is to provide means for holding flexibleplates,'

firmly and evenly, to printing beds or rollers.

With these and incidental objects in view, the invention consists ofcertain novel features of construction and combination of parts, theessential elements of which are hereinafter described with reference tothe drawings which accompany and form a part of this specification.

In. the drawings, Figure 1 is a plan view of my improved printing plateholding device showing the locating lines thereon. Fig. 2 is a sideelevation of a portion of the plate showing its relation to a portion ofa machine for making photo printing plates. Fig. 3 is an enlarged detailof a portion of the board shown in Fig. 1 with the locating linesomitted. Fig. 4: is an enlarged sectional view taken on the line AA,Fig. 5. Fig. 5 is a wiring diagram of the same board. Fig. 6 is a planview of a rotary press roller showing the manner of leading theelectrical current thereto, and Fig. '7 is a sectional view of theroller taken on the line BB,

The entire magnetic board, Fig. 1, has lines A running across thesurface in one direction and lines surface in the other direction, theselines being spaced apart one inch, or any other suitable distance.

Lines A. and B also run over the surface of the board being shown,however, in only a portion of the surface in Fig. 1, it being understoodthat the finer divisions may cover the entire surface in the samemanner.

In setting up the printing plate on my improved machine for makingprinting plates described in my .copending application, Serial #56931,filed October 20th, 1915,

I sheet of soft iron, it is B running across the the plate is positionedon the vertical board, the switch 1 turned on, and the plate will betightly held against the board by. the magnetic action hereinafterdescribed and the location of the plate will be recorded in a recordbook kept for that purpose.

When the plate is moved to the other vertical and horizontal positionsas de scribed in my copending application heretofore mentioned, a recordof each position iii) is taken so that at any time in the future theplate may be positively located and will check exactly with its originallocation in the machine.

The printing plate holding device has running across the face thereofstrips 2, Fig. 3, preferably of steel. instead of steel, I may employsoft iron, but the steel strips when sutliciently hard retain sufiioientresidual magnetism to maintain the plates in positionif the currentshould accidentally be turned off. li/[agnetically connected with thestrips 2, by studs 3, Fig. 4, is the core 5 surrounded by theelectromagnetic coil 6 and which, when energized, establishes magneticpoles as indicated by the letters N and S.

A suitable number of coils thus magnetically bridged across each pair ofstrips 2 so the entire surface of the board will comprise a series ofnorth and south poles and thus firmly hold to the surface I of the polesany magnetic material placed thereon. when the switch 1 connecting thecoils 6 to a suitable source of electric energy '7, is closed.

If the zinc plate used, as described in my copending application Serial#56931, is attached by any suitabie means to a flexible evident theplate will be held in a plane surface by the magnetic action of thestrips 2 and thus obviate any possibility of the plate getting out offocus.

In my application, Serial. #56931, I utilized in place of the magneticboard a vacuum board but I prefer a magnetic board as it is simple andmore positive in action, is more easily handled in a dark room and doesaway with the glass plate which has a tendency to distort the plate.

In Figs. 6 and 7, i show means of constructing a roller for a rotarypress in such manner that my invention is applicable thereto and it isreadily seen that the print be held ing plate can, in the same manner,

@EESI' A AILABLE CQPY -tive signal when the coils are actuated, and

by becoming dark When the coils receive no current, serve as anindication to the operator-that the coils are not active.

For use on fiat boards or beds, the lamp is preferably mounted in onecorner, and on rotary presses is preferably mounted near the feedingtable.

, With the roller as shown in Fig. 6, I have suitable collector rings 8connected by suitable brushes 9 to a source of power 10 and by usingcoils constructed as shown in Fig. 4:, I can employ either alternatingor direct current.

The coils 6 shown in Fig. 4 have surrounding the core 5, a copper sleeve11 which operates in a manner Well-known to those skilled in the art andsmooths out the magnetic attraction when alternating current is used, sothe plate will be held firmly f in spite of the fact that during thecycles of alternating current there Will be a time when no current ispassing through the coils;

While I have described my invention and illustrated it in one particularform, I do not wish myself to be understood as confining myself to thisparticular construction,

a's it is evident that myihv ention may be embodied in various Ways anddifferent all types of printing presses and electromagnetically holdingsaid magnetic plate and through said magnetic plate, said zinc plate.

I 2. In-a printing plate device, the combination of a board, graduationson said board for locating a plate thereon, a plate comprising an ironflexible sheet and a zinc flexible sheet bound together in intimatesurface contact, and electromagnetic means for holding said plate tosaid board.

3. In a printing plate device, the combination of a surface for holdinga plate thereon, graduations on said surface for 10- cating printingplates thereon, a flexible zinc and a flexible magnetic plate'joined inintimate contact, and electro-magnetic means associated with saidsurface for holding thereon said magnetic plate carrying said zincplate.

4. In a print plate device, the combination of a board for receivingprint plates, graduations on said board for locating printing platesthereon, electro-magnetic means for holding magnetic plates to saidboard, a sensitized flexible sheet and a flexible iron sheet bound tosaid sensitized sheet in intimate contact.

HERMAN c. BOEDICKER.

